Synthesis and evaluation of anticancer natural product analogues based on angelmarin: targeting the tolerance towards nutrient deprivation

Inspired by nature: Angelmarin is an anticancer natural product with potent antiausterity activity, that is, selective cytotoxicity towards nutrient-deprived, resistant cancer cells. Through structure-activity relationship studies, three analogues were identified as lead compounds for the develpoment of molecular probes for the investigation of the mode of action and biological targets of the antiausterity compounds.     

PARTICLE SIZE,SOLVENT, OXYGEN,TEMPERATURE AND PRESSURE EFFECTS ON THE CONTENTS OF INSOLUBLE FRACTIONS FROM SOLID VACUUM RESIDUA

ABSTRACT

n-Heptane insoluble contents were determined for an extraheavy-oil vacuum residue, one petroleum and one coal pitch as a function of particle size. This variable was found to affect the yields of insoluble material, aspect which was also observed during extractions carried out with aromatic and halogenated solvents. The precision of results was observed to be independent on the operators. A study was carried out to determine the effect of sample drying time on fraction yields. It was found that maltene fractions were strongly dependent on this variable, whereas asphaltene fractions were totally independent

Predissolution in aromatic solvents proved worthless from the repeatability point of view. However, predissolution of the oil residue in CH₂Cl₂ followed by filtration and asphaltene precipitation with simultaneous solvent removal, was deemed to be a suitable technique to remove mineral matter and isolate asphaltenes in a single step

Sample oxidation during asphaltene precipitation and isolation was detected by gravimetric and spectroscopic techniques. This fact is very important since common precipitation techniques do not address this issue

Preliminary accelerated extraction experiments carried out with pitch samples at high temperature and pressure, revealed that this approach can be a very interesting research tool to investigate solubility properties.     

Novel Use of Scanning Electron Microscopy for Detection of Iron‐Induced Morphological Changes in Human Blood

Fibrinogen is key to the maintenance of hemostasis and is an acute phase protein that is part of the coagulation cascade of proteins. It plays a fundamental role in inflammation, particularly as indicator for a proinflammatory state and is a prominent marker for developing vascular inflammatory diseases. The ultrastructure of fibrin nets can be studied using scanning electron microscopy (SEM) with the addition of thrombin to plasma. In inflammatory conditions such as thromboembolic ischemic stroke and diabetes, the fibrin networks are changed to from dense matted fibrin deposits (DMDs) instead of typical netlike appearance. Similar DMDs can also be induced with the addition of FeCl₂ and FeCl₃. Importantly, the iron‐induced DMDs look similar to those from patients with prothrombotic conditions. Excessive or misplaced tissue iron now is recognized to pose a substantial health risk. The current research therefore investigates the establishment of a laboratory fibrinogen model to study that might mimic fibrin fiber generation that is achieved using plasma from healthy and diseased individuals. Furthermore, to determine whether the addition of iron to purified fibrinogen will show DMDs and whether hydrophilic agents can prevent them. We conclude that SEM is a very effective tool for the visualization of circulatory consequences of the interaction of iron‐induced hydroxyl radicals with human fibrinogen. Furthermore, this novel fibrinogen model provides a convenient method to study the interactions of the intramolecular and intermolecular hydrophobic forces responsible for the maintenance of the tertiary structure of native fibrin(ogen) and the prevention of iron‐induced DMDs formation by hydrophilic agents. Microsc. Res. Tech. 76:268–271, 2013. © 2012 Wiley Periodicals, Inc.     

Performance of fluorene and terthiophene copolymer in bilayer photovoltaic devices: The role of the polymer conformations

We report experiments using fluorene and terthiophene copolymer as the active layer in bilayer devices with C₆₀. The highest short circuit current, open circuit voltage and power conversion efficiency upon AM1.5 illumination were 6.8 mA/cm², 0.68 V and 2.33%, respectively. Density functional theory analysis was used to identify the most stable configurations of the terthiophene moieties in the polymer: the most stable form has the thiophene rings in the alternate configuration (anti) and the second conformation has the thiophene rings pointing to the same direction (syn). Comparing theoretical results with measurements of absorbance, X-ray diffraction, and X-ray reflectometry experiments, we conclude that the annealing treatment produces conformational anti to syn transition along the backbone of poly[9,9′-n-dihexyl-2,7-fluorene-alt-2,5-terthiophene] (LaPPS45). The syn segments of the chain condensed then in a lamellar ordered structure which increases the degree of crystallinity of the annealed samples and improve the light harvest at long wavelengths. From absorption measurements of films submitted to different annealing temperatures and with the help of theoretical calculations we propose a “wave-like” aggregation pattern to the syn segments in those lamellas.     

Multiple degree elevation and constrained multiple degree reduction for DP curves and surfaces

In this paper, the problem of single and multiple degree elevation and reduction for DP curves and surfaces is considered and expressed in matrix representations. Using monomial matrix representations of the univariate DP polynomials, single and multiple degree elevation matrices can be derived by minor extension of this monomial matrix. Given this result, matrices of constrained single and multiple degree reduction can be readily obtained. Finally, important and sufficient conditions for degree reduction can also be found from these resulting matrices.     

German and Norwegian policy approach to residential buildings’ energy efficiency—a comparative assessment

Buildings in private and domestic use are responsible for about 30% of the global greenhouse gas emissions attributable mainly to their need for heating and cooling energy. This corresponds to about 40% of the global final energy consumption. Therefore, a viable implementation of building energy efficiency policies is inevitable to realize a transformation of the energy system to mitigate climate change. Within the building sector lies a huge potential for emission reduction consisting in the renovation of the existing building stock and climate-friendly building guidelines applicable to new constructions, both adapting CO₂-neutral technology solutions. However, as there are several different pathways leading to a decarbonized energy system, there is always the question which political and technological solutions are most efficient, effective, and feasible. This paper aims to analyze building efficiency policy measures and instruments and the related technological solutions in two front-runner countries of the energy transition, possessing different structural conditions: Germany and Norway. We hence apply a comparative approach which allows us to present and assess the policies in place. The paper answers three research questions: (1) Which policies prevail in Germany and Norway to foster the deployment of energy efficient and decarbonized solutions for residential buildings? (2) How do these policies respond to country-specific barriers to the energy transition in the building sector, and (3) What effects do they have on the actual implementation of technological and societal solutions? This research provides a new insight to the highly relevant topic of energy efficiency in buildings in the context of international Intended Nationally Determined Contribution benchmarking and discusses some unsolved trade-offs in the translation of the global climate governance into the national building sector.     

Magnetic Resonance Imaging Correlates of White Matter Gliosis and Injury in Preterm Fetal Sheep Exposed to Progressive Systemic Inflammation

Progressive fetal infection/inflammation is strongly associated with neural injury after preterm birth. We aimed to test the hypotheses that progressively developing fetal inflammation leads to neuroinflammation and impaired white matter development and that the histopathological changes can be detected using high-field diffusion tensor magnetic resonance imaging (MRI). Chronically instrumented preterm fetal sheep at 0.7 of gestation were randomly assigned to receive intravenous saline (control; n = 6) or a progressive infusion of lipopolysaccharide (LPS, 200 ng intravenous over 24 h then doubled every 24 h for 5 days to induce fetal inflammation, n = 7). Sheep were killed 10 days after starting the infusions, for histology and high-field diffusion tensor MRI. Progressive LPS infusion was associated with increased circulating interleukin (IL)-6 concentrations and moderate increases in carotid artery perfusion and the frequency of electroencephalogram (EEG) activity (p < 0.05 vs. control). In the periventricular white matter, fractional anisotropy (FA) was increased, and orientation dispersion index (ODI) was reduced (p < 0.05 vs. control for both). Histologically, in the same brain region, LPS infusion increased microglial activation and astrocyte numbers and reduced the total number of oligodendrocytes with no change in myelination or numbers of immature/mature oligodendrocytes. Numbers of astrocytes in the periventricular white matter were correlated with increased FA and reduced ODI signal intensities. Astrocyte coherence was associated with increased FA. Moderate astrogliosis, but not loss of total oligodendrocytes, after progressive fetal inflammation can be detected with high-field diffusion tensor MRI.     

In-situ preparation of polymer scaffolds in retarded cement slurries: An emulsion templating approach for rapid, on-demand strength development

We demonstrate in this communication that stable high internal phase emulsions consisting of a majority dispersed cement slurry as aqueous phase and a continuous but minority monomer oil phase can be produced. Polymerisation of the monomer phase using both a conventional thermal method as well as by fast setting using carbon fibres as resistance heaters results in bicontinuous polymer cement hybrid materials. We found that a reduction of the polymerisation time from 24 h to 90 min did not affect the physical characteristics, such as density and porosity, of the polymer-cement hybrids but results in a decrease of the crush strength and a significantly reduced elastic modulus.     

Social engineering and participation in Anglo-Swedish housing 1945–1976: Ralph Erskine's vernacular plan

This article appraises the career of architect Ralph Erskine focusing on the context for his contribution to Swedish and British social housing and planning. Erskine's formative experience during the 1930s and his subsequent transnational career are utilized to explore the mutual influences of planning ideals across national boundaries. The Garden City ideal, Functionalism and the urban village concept are considered for their long-term contribution to his work. In addition, vernacular architecture and participatory planning are explored as influences on the evolution of his community architecture vision by the 1970s. Drawing on evidence from urban developments in Britain and Sweden, the discussion demonstrates that Erskine's cultural transfer of international planning ideals essentialized aspects of British and Swedish historical culture. The article concludes with a discussion of the 1970s and Erskine's role in the redevelopment of Byker in Newcastle upon Tyne. This process was hailed as a pioneer moment in the English community architecture movement. However, this study demonstrates that Erskine should be distinguished from the grassroots activism of the community architecture movement. Rather the discussion emphasizes that his participatory planning was underpinned by a structural tension between social engineering and democratic participation that was generated and reinforced by his transnational career.